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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

14805 results found.

  1. GRB 011130 I-band Observation
  2. GRB011130 (XRF011130) SDSS PT i-band observations
  3. GRB011130 (=XRF011130): Revised Localization of an X-ray
  4. GRB 011121
  5. GRB 011121: J-band observations
  6. GRB010921 - Milagro GeV/TeV Observations
  7. Correction: GCN1157 (GRB 011121)
  8. GRB011121: UBRI Observations
  9. GRB 011121: Radio Observations
  10. GRB 011121 J-Band Astrometry
  11. GRB011121: possible redshift, continued decay
  12. GRB011121: fading behavior
  13. GRB 011030: TNG K-band observation
  14. XRF011030: J and K band observations
  15. XRF011030: Chandra Observations
  16. GRB 011030: K-band observations
  17. GRB011030: Z-band observations
  18. GRB 011030 R band observations
  19. GRB 011030 I-band Observation
  20. The X-ray Flash 011030 ('GRB 011030')
  21. Non-triggered burst 011030 ("GRB 011030")
  22. The Radio Afterglow from the X-ray Rich GRB 011030
  23. GRB 970828: HST Observations of the Host Galaxy
  24. GRB 970828: HST Observations of the Host Galaxy
  25. GRB010921, optical observation
  26. Optical observation of SGR 1806-20 at the 6-m SAO telescope
  27. GRB 011030 K-band Observations
  28. GRB010921, optical observations
  29. GRB010921, optical observation at early time
  30. GRB 010921, I-band observations
  31. GRB010921: Spectroscopy of the Host Galaxy
  32. Optical Observations of the field of HETE trigger #1793/GRB 011012?
  33. GRB010923 as seen by BeppoSAX GRBM
  34. GRB010928(=H1770): Localization of a Long GRB by HETE
  35. GRB010923(=H1764): A Short Duration GRB Detected by HETE
  36. GRB010921, negative optical observations
  37. H1761: A Bright GRB Detected by HETE
  38. HETE Trigger #1760 (GRB 010920B?): new optical source = asteroid
  39. HETE Trigger #1760 (GRB 010920B?): a new optical source
  40. HETE Trigger #1759 (GRB 010920?) optical observations
  41. GRB001109, Host Galaxy Spectroscopic Observations
  42. GRB 010222: HST observations -- host galaxy and late-time decay
  43. BeppoSAX/GRBM detection of GRB 010801
  44. Dramatic Increase in the Rate of X-ray Bursts Reported by HETE
  45. BeppoSAX/GRBM detection of GRB010728
  46. GRB 010222 - WHT BVRI images
  47. SGR1900+14 burst seen by HETE: BeppoSAX data
  48. GRB 010629 Optical Observations
  49. GRB010629: Optical Observations
  50. SGR1900+14: High Fluence Burst Localized by HETE
  51. GRB010629, optical observations
  52. GRB010629: A Burst Localized by HETE
  53. SGR1900+14: Second Burst Localized by HETE
  54. SGR1900+14: A Burst Localized by HETE
  55. SGR1806-20: A Second, Intense Burst Localized by HETE
  56. SGR1806-20: Localization by HETE
  57. GRB010518: a faint BeppoSAX detection
  58. X-ray precursors to the large flare from SGR 1900+14
  59. SGR 1900+14 : RXTE observations
  60. BeppoSAX/NFI Follow-up Observation of SGR 1900+14
  61. SGR 1900+14: Correction to GCN 1049
  62. Millimeter observation of SGR 1900+14
  63. Chandra Observations of SGR 1900+14
  64. Possible precursor to the SGR1900+14 giant burst
  65. IPN Triangulation of the Giant Flare from SGR1900+14
  66. GRB010412: Optical observations
  67. GRB010412: BeppoSAX GRBM and WFC observations
  68. REVISED LOCATION OF GRB010326A
  69. GRB010324, field photometry
  70. Further Optical Observations of GRB 010324
  71. GRB010326B: Localization by HETE (2nd GRB for this date)
  72. GRB010326: Refined Localization by HETE
  73. GRB010326: Localization by HETE
  74. IPN TRIANGULATION OF GRB010324
  75. Support extension to the BeppoSAX mission
  76. GRB 010222 - HEGRA GeV/TeV Observations
  77. GRB010220 optical obsercations
  78. GRB 010222: High-Resolution Keck Spectroscopy
  79. GRB 010214, I-band data
  80. Sub-millimeter Excess/GRB 010222
  81. GRB 010222
  82. GRB010222 further R-band photometry
  83. GRB 010222: Keck Spectroscopy
  84. GRB010222 further R-band photometry
  85. GRB 010220: Near-IR Observations
  86. GRB010214 follow-up from Hanle
  87. GRB 010222: Near-IR Observations
  88. GRB 010222, Decay Slope Confirmed
  89. GRB010222: Another absorption line system
  90. GRB 010214, Optical Observations
  91. GRB010222, radio observations
  92. GRB010222, optical observations
  93. GRB 010220, simultaneous optical observations
  94. GRB010220: BeppoSAX WFC and GRBM preliminary data
  95. GRB010214, optical observations
  96. GRB010214: BeppoSAX WFC and GRBM preliminary data
  97. GRB 010214: X-Ray afterglow
  98. GRB 010214, Optical Observations
  99. GRB 010214 optical observation
  100. GRB010213, Radio Observations

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